Such a device is known from US 2005/0233077. The known device is used for coating inner surfaces of containers, in particular bottles for holding beverages. The device is integrated in a carousel guiding the containers along a process path whose length is adapted to the necessary processing time, in this case coating time. The process medium or the process media required for treating the container is/are supplied via valves. Each consumer station and each process medium requires a valve of its own. In order to reduce the number of valves, it has already been suggested in this reference that, in each consumer station, two containers should be connected to the junction for a process medium, so that only half the number of valves will be required. Nevertheless, a large number of valves is still necessary, which render the system very expensive.